Glyburide poses high risk for older adults

Earlier this year, The American Geriatrics Society updated the Beers Criteria for potentially inappropriate medication use in older adults. Glyburide was added to this list due to prolonged hypoglycemic side effects more commonly seen in older patients. (1) Comparative studies have confirmed this risk when weighed against glipizide or glimepiride. Both sulfonylureas still provide significant efficacy for patients with type 2 diabetes (a 1 to 2 percent HbA1c reduction).

The prolonged hypoglycemic effects seen with glyburide are due to its ability to continually stimulate insulin secretion in an already hypoglycemic state. This is partially due to glyburide accumulation within the beta cells, which is not seen with other sulfonylureas. Glyburide is also metabolized to active metabolites that further accumulate in patients with renal dysfunction and has been associated with a two-fold increase of hypoglycemia in older patients compared to glipizide. (2) When comparing glipizide against glimepiride, glimepiride offers convenient once-daily dosing, which can improve patient adherence.

Conversion table from glyburide to glimepiride or glipizide (3)

Drug Usual starting dose Comparative daily dose
Glyburide 2.5-5mg QD 1.25mg QD 2.5-5mg QD or
divided BID
5mg QD or
divided BID
10mg QD or
divided BID
20mg QD or
divided BID
Glimepiride 1-2mg QD 1mg QD 1-2mg QD 2mg QD 4mg QD 8mg QD
Glipizide 5mg QD or
divided BID
2.5mg QD 5mg QD or
divided BID
5mg QD or
divided BID
10mg QD or
divided BID
20-40mg divided BID

References:

  1. “The American Geriatrics Society.” AGS Beers Criteria 2012. AGS, 2012. Web. 3 Oct 2012.
  2. Skoff, RA, NV Waterbury, RF Shaw, JA Egge, M Cantrell. “Glycemic Control and Hypoglycemia in Veterans Health Administration Patients Converted from Glyburide to Glipizide.” Journal of Managed Care Pharmacy. 17.9 (2011): 664-671. Print.
  3. Sulfonylurea dose comparison. Pharmacist’s Letter/Prescriber’s Letter 2009; 25(8): 250801